| The treatment rate of municipal wastewater is increasing with the acceleration of urbanization and and reinforcement of environmental awareness. Thus, the amount of sewage sludge production is increasing How to treat the sludge properly and scientifically has become a common concern. In this paper, two kinds of municipal sewage sludge and coal are mixed (the mass mixing ratio of sludge/coal is 1/6) and milled to prepare the sludge coal water slurry. Based on the previous relevant research, the experimental research of coal water slurry is focused on the following aspects:Firstly, the basic characteristics of sludge coal water slurry such as slurribility,rheology and thermal analysishave been studied, the results showed that the sludge coal water slurry could be a good product when the dispersant ratio was 1.2% and the stabilizer ratio was 0.1%. Moreover the rheology could meet the standards of state technical specification of coal water mixture. The results indicated that the ignition temperature of S-CWS was about 10℃～20℃lower than ordinary CWS. Nevertheless, the combustion stability declined. According to comprehensive burning index S, the combustion characteristics of S-CWS were better than that of CWS.Secondly, the effect of the kinds of sorbents on the slurribility characteristics of sludge coal water slurry had been analyzed. The results showed that sulfur-retention agent had little effect on the rheology of S-CWS, which still appeared as pseudoplastic fluid. Nevertheless, the viscosity of S-CWS increases. The influence of CaCO3 on the rheological behavior of S-CWS is less than that of Ca(OH)2, the Ca/S molar ratio should be controlled below 1.5. At the same time, tests of combustion of sludge coal water slurry (S-CWS) were conducted in a fixed bed oven. The results showed that the optimum Ca/S molar ratio of sludge coal water slurry (S-CWS) should be 1.5 under experimental conditions.Thirdly, combustion contrasting test of sludge coal water slurry and Datong coal water slurry were conducted in 3.2MW furnace. Combustion characteristics, slagging characteristics and pollutant emission characteristics were researched. The results showed that the combustion of S-CWS was satisfactory, which is better than Datong bituminous coal-water slurry. The slagging situation was not serious, and the ash deposition rate was 61.54gm-2 min-1, which was lower than the Datong CWS. The concentration distribution of SO2 and NOx in flue gas was 1038 mg/m and 1118 mg/m3 respectively, which were at high level. The conversion rate of heavy metals into the flue gas was not high, and the share was usually among 10%40%.However, Hg is strong volatile element and the conversion rate of fuel-Hg to gaseous state have reached 77.84%.
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